Saturday, May 7, 2011

All Together Now – Part One


In the previous articles in this series, we learned how to do a roll, maybe even some consecutive rolls (Doing The Roll), some loops (Loops) and found out that that strange stick on the left side of the transmitter actually does work something, the rudder (Using The Rudder). All this has been fun and challenging. If you were like most of us, learning to consistently fly these maneuvers well, and right in front of the pilot in wind, took several months. It was not as easy as it looked. But the effort made all of us better pilots while increasing our wind flying skills.

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Photo 1

But now, it is time for something completely different! It is time to take these new skills and start putting maneuvers together. Why? Because learning how to group and place maneuver sequences will continue growing our piloting skills. Right now, right here, is the danger point in a model pilot’s, and even in a full-size pilot’s, piloting career.


Photo 2 Photo 3

Too many pilots stop learning at this point. After about a season, most pilots are content to fly a few rolls, maybe do a loop somewhere, fly inverted along the runway, do some stall turns and even enjoy making some crosswind landings. Well, sometimes they enjoy it. But they stop learning at this point. True, many go on to pilot more difficult to fly aircraft like scale replicas (photo 2) and quick-acting aerobatic airplanes (photo 3). This helps some and every new airplane a pilot flies teaches new things.

But the pilot has not learned to truly think, fly and look ahead of the aircraft. The ability to automatically think two steps ahead of the airplane while seeing the sky in front and having the absolute confidence that you know what should happen next, has yet to develop. The learning processes required to fly maneuver sequences are what builds these vital skills.

So, be happy you can fly precise individual maneuvers. But please don’t stop here. There is so much more waiting for you just a few steps ahead. This next growth step in a pilot’s career is so important that this plea will be repeated in Part II of this series as well.

Part II? Yes, this is a two-part series because, by the end of it, you will be able to fly just about any airplane, from any field, in any wind, in any attitude and never even realize just how good a pilot you have become. By the end of Part II, we will have progressed to some quite difficult maneuver sequences. In this section, the basics of sequencing are studied. Basic? Yes. Easy? Not really.


Photo 4

As you will find, flying even the easiest maneuver sequence will be challenging. It can’t get much easier than flying a level, straight line can it? Surprise, of all the maneuvers in a sequence that can be flown, the most difficult maneuver is to fly a straight line. Really, I’m not kidding. You’ll see!

TAKE OFF


Photo 5

Before you even start your engine take a look at your field for some landmarks (I know you pilots in the Midwest don’t have trees and mountains but, find some telephone poles or barns or something).


Photo 6 Photo 7

Find something in the center of your flight path (photo 7) —move a little if you have to—and something at both ends of your flight path. Any marker that is about 60 degrees or so, on both sides, should do well (photo 6). Now, your maneuver area will total about 120 degrees. Remember your three markers. Even better, draft a fellow pilot to call the center and the ends of the maneuver area for you. It’s always best to fly with a co-pilot anyway.

OK, start the engine and have your copilot carry it out to the middle of the runway for you. WOW, now you’re starting to look like a pro! Have the airplane placed about 50 to 80 feet back from that center line you “marked: earlier. Your copilot did place the airplane pointing upwind, right? Don’t get nervous, the fun will start soon. Now we finally get to the actual takeoff. Slowly and smoothly accelerate and break ground right at the center line. COOL!

Manage the throttle to keep the airplane on the ground until the center liftoff point. If the airplane is reaching flying speed too soon, lower the throttle 3-4 clicks. It is OK to lower the throttle during the takeoff run. Most Basic and Advanced Trainers will easily break ground at 60% throttle or less.

In fact, takeoffs are easier to manage at about 75% throttle. We all want to avoid that sudden leap into the air on takeoff. At full throttle, it is difficult to manage elevator input to assure a smooth, steady climbout. Just a little too much “up” and the airplane leaves the ground as if it had a rocket booster. At lower throttle settings, it is easy to gently rise from the ground and hold a steady climb. Once the climb angle is established, most trainers will want that unused 25% throttle back to hold the steady climb without losing too much airspeed. So advancing to full throttle is a good idea at this point.


Photo 8

Climb at a shallow angle (photo 8) until you are about 50 feet high and then execute a 90 degree turn away from the flight line. Make it a shallow bank and slow, smooth turn. Flying directly away from the flight line, wait till you are about 200 or so feet past where you will be flying. By the way, you will be flying about 75 to 100 yards out from yourself for the purpose of this exercise.


Figure 2

Now, make a 270-degree turn back toward the maneuver flight line you will be flying. Now you are going downwind. Go all the way past the center toward the downwind marker you found earlier. Do any required trimming during this “return” flight. When you get near the downwind 60-degree marker you will do a ‘turnaround’ maneuver to get yourself turned around back into the wind, but still on the original maneuver flight line heading back towards the center marker.

I suggest flying a 1/2 Reverse Cuban Eight as the first turnaround maneuver. Don’t worry, it isn’t all that hard—you don’t even have to do a quality maneuver. This is just to get you turned in the correct direction (upwind) and on the same line you took when flying downwind. That line will be your maneuver flight line for the rest of this exercise. The important part of this maneuver is to get back onto the same maneuver line that your airplane was on when heading downwind.

The maneuver is diagramed in Fig. 3, but is much easier to fly that it is to picture. A 1/2 Reverse Cuban Eight is performed by just pulling the airplane up into a 45-degree climb. In the middle of the climb, perform a 1/2 roll to inverted and hold some down elevator to maintain that 45-degree climb angle. Then pull, use up elevator, a 5/8 loop to return to level, upright flight heading upwind along the same downwind entry line you just flew into the maneuver.

Don’t worry about getting the ½ roll to upright flight exactly in the middle of the straight line. Do worry about pulling out of the loop to level flight. There is just one key to making sure your airplane exits on the same entry line; you must keep the wings level throughout the maneuver. Even more importantly, the wings must be level before pulling into the 45-degree up line. Before starting any maneuver from level flight, always, always, always, level the wing first. Do this and the maneuver will be well on its way to being perfect.

As you finish up the maneuver, you will be ending the Takeoff Sequence and starting the first maneuver of a beginning sequence (or any other word you might like to assign to this devilish problem).

I mentioned before that learning to fly maneuver sequences will increase your piloting skills. But there is another reason to learn sequencing. Before we start on the first sequence we might take the time to think about this second reason. Why in the world would you want to do this stuff to yourself? Why not just keep flying and enjoying yourself by ‘boring holes in the sky’

For me, and for many other more experienced pilots, the answer is: because there are only so many holes you can bore before it gets Booorr-ING.

Yes, boring. In anything I do, I choose to do it well. As well as I can. I have been flying model airplanes, on and off, since I was 10. Now I’m 66. Pretty soon I will become a good flyer. Soon, I will be as good as I can be; and then I can die. I’ll just need another 66 years.

I’m fond of saying that this sport is deep. There is so much to do and so many directions to take that one lifetime is not nearly enough. But let it get boring and I’m out of here. The same might be true for you. How many new fliers learn how to safely takeoff and land plus do a few maneuvers and then you never see them at the field again? They have become bored and moved away to something else without ever having known just how deep and rewarding this sport truly is if it is given the chance. OK, speech over and on to the first maneuver sequence!

STRAIGHT FLIGHT

How much easier can flying be? Just point the airplane in a straight line and let it fly. Easy. I bet that your first attempts at the full Takeoff Sequence outlined above proved just how hard flying a straight line truly is. The turnaround portion of the Takeoff Sequence always reveals just how un-straight (hope that is a word) your flight path was. If the entry line to the ½ Cuban Eight was pointed at an angle to the flight line, the ½ Cuban Eight will likely exit on a line that is the reciprocal of the entry angle. In other words, the exit line points towards the pits or the far mountains instead of exactly back on a return line that is parallel to the maneuver flight line.

Learning to fly a straight line requires calm wind conditions and a good friend. In fact, it needs a very good friend. Because this person needs to stand around being bored for 3-4 flights while coaching you to fly straight. To fly a straight line parallel to the maneuver flight line, the pilot must know how the aircraft will appear when it is doing so. In order for the pilot to learn just how the aircraft appears from the pilot’s position when flying a straight line parallel to the maneuver flight line, it must be flown that way. This is a real Carch-22 situation.

The solution is for a friend to stand well to one side of the pilot, usually about 200 feet, and call out corrections as the airplane flies along the maneuver flight line. From this vantage point, the friend, now a Coach, can see what line the airplane is actually flying and offer corrections to the pilot.

A loud voice is helpful but even better is using the newer personal communication devices sold in most stores for less than $20. These devices operate on a frequency far removed from those used for aircraft control. And the pilot only listens to the Coach, never transmits, so interference is impossible. After 3-4 flights, the pilot will start to recognize the airplane’s appearance when flying a straight flight line and the coaching will no longer be needed except as an occasional refresher.

This all works great when the wind is calm. Unfortunately, the wind is not always calm and it is now blowing at 10 mph in a direction across the maneuver flight line. This crosswind is not my doing; that’s just what really happens when you are trying to fly a straight line. You are going to have to use the rudder to point the airplane slightly into the crosswind just at the start of the maneuver flight line.

Like a rowboat crossing a stream, the airplane must be headed slightly into the wind in order to fly a straight line over the ground. Knowing just how much angle into the wind is needed comes from practice and lots of it. Remember, constant corrections will be needed over the whole 120 degrees as airspeed and wind speed/direction changes! This takes even more practice.

Many RC pilots only fly when the winds are gentle and right down the runway. That is fine for them. Of course they don’t fly very much, that’s their choice, not ours. Let’s fly that wind. When rolling out of the 270-degree turn, level the wings and offset the rudder in the same direction the wind is coming from and do your best to get a straight line without any wobbles or lurches. Holding a wingtip down into the wind also might work but makes the return flight look bad and will mess up any maneuver flown from this banked condition. Keep the wings level and point the fuselage into the wind.


Photo 9

It is difficult to show the fuselage angle in a photo. But photo 9 gives it a good try. Note that the wings are level in the inverted position. Look carefully, click on the photo to enlarge, and you should note that the aircraft’s nose is pointed slightly inside, towards the pilot position, to compensate for the wind’s blowing out, or away from the runway. Imagine how difficult it would be to try using the wings to compensate for the crosswind in this position. Every small elevator change to hold level inverted flight would move the airplane off to the side as well. Use the fuselage angle instead.

If you can do this after just one or two tries you don’t need this column. Go on to Part II of this series. You should be in one of the upper levels of Precision Aerobatic or IMAC competition. For us normal humans, it takes practice to get a reasonably straight line. If your airplane has roll coupling, meaning it also banks when rudder is applied, you will need to also use opposite aileron input to stop any unwanted roll during the brief rudder application period. Yes, it is complicated. OK, now we are nearing the other side of the maneuver flight line and need to get ready to do the next maneuver inside the 60 degree marker.

ONE-HALF REVERSE CUBAN EIGHT

When you are about ¾ the way upwind on your straight flight out, start the 1/2 Reverse Cuban Eight maneuver by establishing a 45-degree up line. Half way up you will do a half-roll and keep the same 45-degree up line now inverted. When you have completed the other half of the up line, you will execute a 5/8th loop by pulling up on the elevator (now you’re going down) and finishing up at the same level you started this maneuver. This is a neat looking maneuver but it is power hungry. If you only have the engine recommended as the lower limit of your airplane you will have to make sure you do all vertical lines lower than what might look to be optimum. That is all right, doing the maneuvers so they look good is the thing we’re after.

To make the maneuvers look their best you will want to make all the loop segments the same diameter. That is, the change from straight flight out to the 1/2 Reverse Cuban Eight 45-degree up line is a 1/8th loop segment as is the 5/8th loop segment when you reach the top and loop back to level flight. That amount of expertise will take a lot of practice. For now, discipline yourself to look for straight lines and reasonably smooth loop segments. Now, lets move on to the next maneuver.

The completed Takeoff Sequence is detailed in Fig. 6:

STRAIGHT FLIGHT BACK

I’m not going to say very much about this maneuver except to do the same thing as the straight flight out. Oh yes, do it in the opposite direction—downwind. Practice, practice, practice! Are we having fun yet? I hope so. Remember when you first started this sport? You couldn’t even get around a 90 degree turn without the instructor taking over. Now you are doing more than 90% of RC pilots ever accomplish.

And there is still more to come. Before moving on to more advanced maneuver sequences in Part II, there are a couple of maneuvers you should practice now that you can fly a straight line.

HALF CUBAN EIGHTS

You most likely have done A Half-Cuban Eight before but may not have realized it has a name. (If you want to know what a full Cuban Eight is, see Part II.) This maneuver is performed as the turnaround maneuver for the Takeoff Sequence you just learned above. After the straight flight back, use the ½ Cuban Eight to turnaround again before reaching the 60-degree marker and head downwind back towards you. Remember to fly that straight line.

That 60 degree end marker is not critical. At this point, it is more of a suggestion than a rule. Don’t worry about it too much, as it is there only to keep your flight within easily identifiable bounds.

For those of you unsure of what a 1/2 Cuban Eight is, here goes: Straight and level flight to nearly the end marker, pull up into a 5/8ths loop segment to a 45-degree down line, the airplane is inverted at this point, followed by a half roll to upright in the middle of the 45-degree down line. Complete the down line and pull a 1/8 loop back to straight and level flight again ready to do the next (centered) maneuver. Wow, that center maneuver comes up fast.

TWO INSIDE LOOPS.

After the half Cuban eight, get ready to do a full loop right on that center marker you sought out earlier. Try to make the loop nice and round—not egg shaped. Refer to the earlier article in this series about doing loops.

As soon as the first loop is finished, do another one right on top of the first. Try to superimpose the second loop on the first. Remember; practice, practice, practice. At the end of the two loops, return to straight and level flight just as in the ‘straight flight out’.

The completed simple maneuver sequence appears in Fig. 7:

You must continue to compensate for any crosswind during this entire short maneuver sequence. The amount of fuselage angle to hold will constantly change with airspeed. Your airplane will lose airspeed during the climbing sections like the loops and up lines. The slower airspeed means applying more rudder input into the wind to increase the fuselage angle.

Similarly, airspeed will increase in the down portions of the loop and 45-degree down lines. Less fuselage angle is needed for wind correction. Use the rudder to decrease the fuselage angle during these high-speed portions of the maneuvers.

No one gets all these corrections perfect all the time. Not even the World’s best Precision Aerobatic and Scale Aerobatic pilots are 100% perfect. That’s why competition scores vary among the top pilots on every flight. Even they make mistakes flying these simple sequences, or “patterns.” However, the top pilots are very good at hiding such mistakes and excellent at recovering from them with minimal damage to the pattern being flown.

As you practice this more, your recovery abilities will also improve. Fly out of your box and land. OK, breathe. Notice how I just said “land.” Remember when that was hard to do? Now, after constantly correcting for crosswinds, adjusting flight lines with rudder and paying attention to wing and fuselage positions, landings in any wind become so automatic that you don’t even think about it. See, you are getting better already. Imagine what a few more practice sessions will do for your piloting ability.

As you conquer these series of maneuvers you will gain confidence and the ability to handle your aircraft in any attitude. You will become one of the better fliers at your field.

A note about instructors:

Not all primary flight instructors will be able to give you much help in your new endeavors. What you might do if your regular instructors do not have the expertise is to seek out some competition Precision Aerobatic (Pattern) or IMAC pilots and ask them for help. Attend a Precision Aerobatic event and watch what you have been practicing in action. If there are some nearby competition pilots, ask them for help.

You are now going into the realm of defining your flight. Plan what you are going to do and then do it. Know that 90% of pilots do not do this, not because they are not able but because they do not wish to improve. More likely, they want to fly better, but just do not know how to go about learning. If so, let them know that this article series is here on Sport Aviator and just as available to them free, as it was to you.

I don’t know about you but I know, for myself; good enough is not good enough. And better is better than not. Once these simple maneuvers are mastered, or at least getting better, go on to Part II of this series for some really challenging, but still simple, maneuver sequences.

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